The present invention relates to a new and improved construction of a controlled deflection roll.
Generally speaking, the controlled deflection roll of the present invention is of the type comprising a stationary roll support and a roll shell rotatable about the stationary roll support. The roll shell is supported upon the roll support by means of at least one support or pressure element which acts upon the inner surface of the roll shell by exerting a pressure force.
In controlled deflection rolls of this type, for instance as have become known in this technology from U.S. Pat. No. 3,802,044, granted Apr. 9, 1974, there are employed either metallic shells or jackets, usually formed of cast iron, or soft shells formed of rubber or a rubber-like plastics material. These roll shells were fabricated in their entirety from the relevant material.
However, under certain circumstances it is readily possible for quite different requirements to be placed upon the inner surface and the outer surface of the roll shell. Thus, the inner surface must possess certain running properties for its coaction with the support or pressure elements, whereas the outer surface is intended to act upon a material which is to be processed and, as a rule, should be compressed, and thus, in may instances the outer surface of the roll shell should have quite different properties than the inner surface of such roll shell. Additionally, this outer surface frequently is subjected to considerable wear. If the outer surface of the roll shell becomes worn then with the prior art constructions of controlled deflection rolls the entire roll shell must be exchanged. This work is complicated, time-consuming and expensive.